单选题Though trying really hard

问题补充：

单选题Thoughtryingreallyhard,theyacknowledged____atlast.A.defeatedB.defeatingC.having defeatedD.having been defeated

答案：

D解析考查acknowledge用法。承认做某事acknowledge doing sth. acknowledged having done表示动作已经发生句意为，尽管很努力地尝试了，他们还是最终成人被打败了。